<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
    <script type="text/javascript" charset="utf-8">
        //分支单体
        var Ext={};
        var def = true;
        Ext.More = (function () {
            //火狐浏览器内部的一些配置
            var objA={
                //属性1
                attr1:'FF属性1'
                //属性2
                //方法1
                //方法2
            }
            var objB={
                //属性1
                attr1:'IE属性1'
                //属性2
                //方法1
                //方法2
            }
            return (def)?objA:objB;
        })();
        alert(Ext.More.attr1);
    </script>
</head>
<body>
</body>
</html>